 Entropy of activation

The standard molar entropy difference between the transition state and the starting reactants, at the same temperature and pressure, with specified standard states, in transition state theory.^[ref]

The term "entropy of activation" refers to the concept associated with the transition state theory of chemical reactions. It deals with the changes in entropy that occur as reactants transition to products through a high-energy transition state. In the context of a chemical reaction, the entropy of activation can be understood as follows: 1. **Transition State Theory**: This theory posits that reactants go through a high-energy transition state before forming products.